[2008, C++, Linux] Highlights common human-understandable patterns to eliminate candidates, using strategies up to
swordfish/y-wing/coloring. Includes a command-line solver that outputs postscript or SVG step-by-step solution
guides, and includes a GTK+/Cairo user interface for interactive solving.

Experiments

Using edge-cases in HTML5 Canvas implementations, it's possible to create images that are different on most
browsers without querying any browser information (via browser detection or reading Canvas pixels).

Not only does this allow creating unique images (try viewing the image to the left on other browsers), but
it's possible to craft the ability to decide what to show for each browser.